Erosion Prediction Calculator

The ErosionPredictionCalculator provides sand erosion assessment for production piping and process equipment using two industry-standard methods.

Class: neqsim.pvtsimulation.flowassurance.ErosionPredictionCalculator

Standards Implemented

Standard	Method	Output
API RP 14E	Erosional velocity limit	Max allowable velocity (m/s)
DNV RP O501	Sand particle erosion model	Erosion rate (mm/yr), cumulative loss

API RP 14E - Erosional Velocity

The API RP 14E erosional velocity formula limits mixture velocity to prevent erosion:

\[V_e = \frac{C}{\sqrt{\rho_m}}\]

Where:

$V_e$ = erosional velocity (ft/s, converted to m/s internally)
$C$ = empirical constant (default 100 for continuous service)
$\rho_m$ = mixture density at flowing conditions (lb/ft3)

C-Factor Guidelines

Service	C-Factor
Continuous (default)	100
Intermittent	125
Solids-free, inhibited	150
With sand production	75-100

DNV RP O501 - Sand Erosion Model

The DNV model predicts material loss rate from sand particle impact:

\[E = K \cdot F(geometry) \cdot \dot{m}_p \cdot V_p^n \cdot f(\alpha)\]

Where:

$K$ = material constant (depends on pipe material grade)
$F$ = geometry factor (elbow, tee, choke, etc.)
$\dot{m}_p$ = sand mass flow rate
$V_p$ = particle impact velocity
$f(\alpha)$ = impact angle function

Supported Materials

Material	Typical Application
`carbon_steel`	General piping
`duplex_steel`	Moderate corrosion environments
`super_duplex`	Severe corrosion + erosion
`13cr`	Downhole tubing
`inconel`	High temperature, corrosive
`titanium`	Seawater systems
`tungsten_carbide`	Choke trim

Supported Geometries

Geometry	Typical Use
`straight_pipe`	Straight pipe sections
`elbow`	Standard pipe elbows
`tee`	Tee junctions
`blind_tee`	Dead-end tees (sand traps)
`reducer`	Pipe reducers
`choke`	Production chokes
`weld`	Girth/field welds

Usage

Basic Erosional Velocity Check

import neqsim.pvtsimulation.flowassurance.ErosionPredictionCalculator;

ErosionPredictionCalculator calc = new ErosionPredictionCalculator();
calc.setMixtureDensity(120.0);    // kg/m3
calc.setMixtureVelocity(12.0);   // m/s (actual velocity)
calc.setApiCFactor(100.0);       // Continuous service
calc.calculate();

double erosionalVelocity = calc.getErosionalVelocity();
double velocityRatio = calc.getVelocityRatio();
boolean withinLimits = calc.isWithinApiLimits();

System.out.printf("Erosional velocity: %.1f m/s%n", erosionalVelocity);
System.out.printf("Velocity ratio: %.2f%n", velocityRatio);
System.out.printf("Within API limits: %s%n", withinLimits);

Sand Erosion Assessment

ErosionPredictionCalculator calc = new ErosionPredictionCalculator();

// Flow conditions
calc.setMixtureDensity(150.0);    // kg/m3
calc.setMixtureVelocity(15.0);   // m/s

// Pipe geometry
calc.setPipeDiameter(0.1524);     // 6 inch (meters)
calc.setWallThickness(10.0);     // mm

// Sand parameters
calc.setSandRate(50.0);           // kg/day
calc.setSandParticleDiameter(0.25); // mm

// Material and geometry
calc.setPipeMaterial("carbon_steel");
calc.setGeometry("elbow");

// Design parameters
calc.setDesignLife(25.0);         // years
calc.setCorrosionAllowance(3.0);  // mm

calc.calculate();

// Results
double erosionRate = calc.getErosionRate();         // mm/yr
double cumulative = calc.getCumulativeErosion();     // mm over design life
double remaining = calc.getRemainingWallThickness(); // mm
String riskLevel = calc.getRiskLevel();              // low/medium/high/critical

System.out.printf("Erosion rate: %.4f mm/yr%n", erosionRate);
System.out.printf("Cumulative erosion (25 yr): %.2f mm%n", cumulative);
System.out.printf("Remaining wall: %.2f mm%n", remaining);
System.out.printf("Risk level: %s%n", riskLevel);

Multiple Geometry Comparison

String[] geometries = {"straight_pipe", "elbow", "blind_tee", "tee", "choke"};

for (String geometry : geometries) {
    ErosionPredictionCalculator calc = new ErosionPredictionCalculator();
    calc.setMixtureDensity(150.0);
    calc.setMixtureVelocity(15.0);
    calc.setPipeDiameter(0.1524);
    calc.setSandRate(50.0);
    calc.setPipeMaterial("carbon_steel");
    calc.setGeometry(geometry);
    calc.calculate();

    System.out.printf("%-15s  Erosion: %.4f mm/yr  Risk: %s%n",
        geometry, calc.getErosionRate(), calc.getRiskLevel());
}

JSON Output

calc.calculate();
String json = calc.toJson();
System.out.println(json);

Output includes:

API RP 14E results (erosional velocity, velocity ratio, within limits)
DNV RP O501 results (erosion rate, cumulative, remaining wall)
Risk assessment (level: low/medium/high/critical)
All input parameters for traceability

Risk Assessment

The risk level is determined by the velocity ratio (actual / erosional):

Velocity Ratio	Risk Level
< 0.5	Low
0.5 - 0.8	Medium
0.8 - 1.0	High
> 1.0	Critical

Python Usage

from neqsim import jneqsim

ErosionPredictionCalculator = jneqsim.pvtsimulation.flowassurance.ErosionPredictionCalculator

calc = ErosionPredictionCalculator()
calc.setMixtureDensity(150.0)
calc.setMixtureVelocity(15.0)
calc.setPipeDiameter(0.1524)
calc.setSandRate(50.0)
calc.setPipeMaterial("carbon_steel")
calc.setGeometry("elbow")
calc.setDesignLife(25.0)
calc.setCorrosionAllowance(3.0)
calc.calculate()

print(f"Erosion rate: {calc.getErosionRate():.4f} mm/yr")
print(f"Risk: {calc.getRiskLevel()}")
print(calc.toJson())